chromium dioxide

• CAS: 12018-01-8
• Catalog Number: ACM12018018
• Category: Main Products
• Molecular Weight: 83.99
• Molecular Formula: CrO2
• Synonyms: Chromium oxide (CrO2)
• Appearance: Solid

Case Study

Magnetic Chromium Dioxide Nanoparticles for Enhancing Magnetorheological Response

Kim M H, et al. Smart Materials and Structures, 2017, 26(9), 095006.

Rod-shaped hard magnetic chromium dioxide nanoparticles were introduced as additives into soft magnetic carbonyl iron (CI)-based magnetorheological (MR) fluids, which effectively enhanced the MR properties and dispersion stability of the MR fluids.
Preparation and analysis of the MR fluid experimental system
· Soft magnetic CI particles (average diameter 4μm, density 7.79 g/cm) were used as magnetic response materials in this work. Silicone oil (viscosity 100 and 1000 cS) was used as the medium. Chromium dioxide (CrO2, density 5.12 g/cm3) with hard magnetic properties was used as an additive to improve the yield stress and dispersion stability. The experimental system of a MR fluid is composed of pristine CI (50 wt. %) and additive (0.5 wt. %) in the carrier oil with a stable dispersed state using a vortex and sonicator for 2 hours each.
· The nanoparticles' magnetic properties were examined using VSM, while the structural features resulting from filling potential cavities and coating CI particles with nanoparticles were verified through SEM analysis.
· Testing on a rotational rheometer under different magnetic field strengths confirmed the enhanced MR properties statically and dynamically. Both fluids, with and without the CrO2 additive, displayed typical MR characteristics indicative of Bingham fluid behavior. This suggests that the additives improve the MR performance.
· The relationship between magnetic field strength and dynamic yield stress was established using a universal scaling equation. Additionally, a dispersion stability test was conducted to demonstrate that the presence of nanoparticles reduces sedimentation in CI-based MR suspensions.

Neutron Diffraction Study of Chromium Dioxide Nanorods

Dho, Joonghoe, et al. Solid state communications, 2010, 150(1-2), 86-90.

To analyze the microstructure and magnetic properties of chromium dioxide (CrO2) nanorods, neutron diffraction experiments were performed at 3.5 K to 450 K. The experimental method involved collecting neutron diffraction data and conducting Rietveld analysis on CrO2 nanorods.
Microstructure and magnetic properties of CrO2 nanorods
· According to the Rietveld refinement analysis, it is suggested that each CrO2 nanorod likely consists of multiple microscopically oriented grains. Notably, the change in the ab lattice constants with temperature is more significant than that of the c lattice constant.
· Additionally, there is evidence of a distortion in CrO6 octahedra above the ferromagnetic transition of CrO2, which intensifies as the ferromagnetic order increases.
· The temperature-dependent resistivity data for the epitaxial CrO2/TiO2 film is closely related to the structural distortion around the ferromagnetic transition temperature. As the temperature decreases, a contraction of the apical bond of CrO6 octahedra perpendicular to the c-axis may lead to the localization of one electron into the lowest xy orbital and the occupation of the mixed (yz±zx) orbitals by another itinerant electron. This mechanism is believed to be responsible for inducing the half-metallic ferromagnetism in CrO2.

Custom Q&A

What is the molecular formula of Magtrieve(TM)?

The molecular formula of Magtrieve(TM) is CrH4O2.

What is the PubChem CID of Magtrieve(TM)?

The PubChem CID of Magtrieve(TM) is 15972932.

What is the molecular weight of Magtrieve(TM)?

The molecular weight of Magtrieve(TM) is 88.027 g/mol.

What are the synonyms of Magtrieve(TM)?

The synonyms of Magtrieve(TM) are "Magtrieve(TM) chromium;dihydrate" and "12018-01-8".

When was Magtrieve(TM) last modified?

Magtrieve(TM) was last modified on December 2, 2023.

What is the IUPAC name of Magtrieve(TM)?

The IUPAC name of Magtrieve(TM) is chromium;dihydrate.

What is the InChI of Magtrieve(TM)?

The InChI of Magtrieve(TM) is InChI=1S/Cr.2H2O/h;2*1H2.

What is the InChIKey of Magtrieve(TM)?

The InChIKey of Magtrieve(TM) is DJCIVHDYINPEKO-UHFFFAOYSA-N.

How many hydrogen bond donor counts does Magtrieve(TM) have?

Magtrieve(TM) has 2 hydrogen bond donor counts.

Does Magtrieve(TM) have a defined bond stereocenter count?

No, Magtrieve(TM) does not have a defined bond stereocenter count.